Sabre saws and especially general purpose electrically driven sabre saws for use by craftsmen and handymen have become popular and versatile tools for cutting wood, light sheet metal, plastic, composition board, and the like. Such saws are known comprising a generally cylindrical housing containing a built-in electric motor which drives a reduction gear train to rotate an eccentric crank pin which in turn is operatively associated with a crosshead mounted for movement with an elongated saw bar in turn journalled for reciprocatory movement generally perpendicular the motor axis. Because the reciprocation of the saw bar and crosshead provides a rapidly varying load to the motor and substantial vibration, various schemes have been devised and attempted to reduce vibration and load variation associated with the reciprocation of the saw bar.
In copending applications Ser. Nos. 103,662, filed Dec. 14, 1979 and 137,928 filed Apr. 7, 1980, assigned to the assignee of the instant application, and hereby incorporated herein by reference, as fully and completely as if reproduced hereat, various aspects of reduced mass saw bar and crosshead designs are disclosed which have been effective to reduce the mass and, therefore, the vibration and shock loading accompanying the reversal of movement of the saw bar. The instant application is directed towards a saw bar and blade holder or chuck assembly which yet further reduces the mass to be reciprocated and which enables the use of a light weight, low mass material such as magnesium as a substantial component of the blade holder or chuck assembly while yet enabling a saw blade, or the like, to be rigidly clamped substantially entirely by steel or steel-like components.